REGULATION AND FUNCTION OF CENTROSOME ASSOCIATED PROTEINS Public Deposited

Downloadable Content

Download PDF
Last Modified
  • March 20, 2019
Creator
  • Plevock Haase, Karen
    • Affiliation: School of Medicine, Department of Biochemistry and Biophysics
Abstract
  • Centrosomes are the main microtubule organizing center in cells, composed of a pair of centrioles surrounded by pericentriolar material (PCM). Centrosomes are a highly organized network of proteins that undergoes dynamic regulation tied to the cell cycle. A major structural reorganization occurs as cells transition from interphase to mitosis. As cells enter mitosis, PCM is recruited to the centrosome. This transition is important for centrosomes to function as a main organizer of the bipolar mitotic spindle. The proteins that comprise the centrosome are not fully known, and it remains unclear how the centrosome’s organization and function are regulated throughout the cell cycle. Here multiple approaches were used to characterize known centrosome components and further define the complex protein interaction network at the centrosome. X-ray crystallography, biochemistry, cell biology and Drosophila and yeast genetics were used to characterize two centrosome proteins that localize to the centrosome during mitosis. CP190, a Drosophila centrosome protein, was shown to interact with MTs and regulate spindle architecture in developing neural stem cells. Detailed work on the c-terminal coiled coil region of STU2, a member of the XMAP215 family in Saccharomyces cerevisiae, unveiled a role for this conserved region in maintaining proper spindle structure. Work on a PCM scaffolding protein, Pericentrin-Like-Protein (PLP) in Drosophila, revealed a role for Calmodulin in stabilizing its protein levels and for proper anchoring of PLP at the centriole wall. Further, a structural rearrangement of PLP concurrent with PCM recruitment was revealed through super-resolution microscopy. Polo phosphorylation sites were mapped on PLP both in vitro and in vivo, suggesting a possible mechanism for regulating PLPs conformation state and thus its ability to recruit PCM. Lastly, BioID and quantitative mass spectrometry were utilized to identify novel components and interactions at the centrosome. BioID of the c-terminal region of PLP identified two components, SkpA and CG7033, known to play roles in spindle architecture, that may recruit PLP to the centrosome or regulate it upon localization. Collectively, the work presented here highlights the complexity that exists at the centrosome and the importance of interactions amongst centrosome components in regulating function throughout the cell cycle.
Date of publication
Keyword
DOI
Resource type
Rights statement
  • In Copyright
Advisor
  • Goldstein, Robert P.
  • Slep, Kevin
  • Rusan, Nasser
  • Kuhlman, Brian
  • Neher, Saskia
  • Redinbo, Matthew R.
Degree
  • Doctor of Philosophy
Degree granting institution
  • University of North Carolina at Chapel Hill Graduate School
Graduation year
  • 2016
Language
Parents:

This work has no parents.

Items